<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        body {
            background-color: lightyellow;
        }
        div {
            width: 32em;
            height: 0.5em;
            font-size: 10px;
            background-image: linear-gradient(
                to right,
                black 0,black 4em,
                transparent 4em, transparent 5em,
                black 5em, black 7em,
                transparent 7em, transparent 8em
            );
            background-size: 8em;
        }
    </style>
</head>
<body>
    <div></div>
</body>
</html>